Acids and bases react to form water and salt in a neutralization reaction.

The general equation for a neutralization reaction is:

```

acid + base → salt + water

```

For example, when hydrochloric acid (HCl) and sodium hydroxide (NaOH) are mixed, the following reaction occurs:

```

HCl + NaOH → NaCl + H2O

```

In this reaction, the hydrogen ion (H+) from the acid combines with the hydroxide ion (OH-) from the base to form water (H2O). The remaining ions, sodium (Na+) and chloride (Cl-), combine to form sodium chloride (NaCl), which is the salt.